In August 2014, public health officials with the Alaska Section of Epidemiology (SOE) received a report of a patient complaining of bitter metallic taste, fever, weakness, cough, and muscle pain 7 hours after introduction of live zoanthid coral into his home aquarium. Palytoxin, a potent toxin known to produce the reported effects, is contained in some zoanthid marine corals.
METHODS:
SOE launched an epidemiologic investigation, during which investigators interviewed exposed persons, obtained five environmental specimens for testing, and provided advice about avoiding continued exposure. SOE collaborated with the Food and Drug Administration’s Center for Food Safety and Applied Nutrition to analyze coral specimens.
RESULTS:
The epidemiologic investigation revealed a total of ten aquarium enthusiasts, or co-inhabitants, reporting similar symptoms consistent with palytoxin exposure in recent years, including multiple employees at an Anchorage aquarium shop. Most of these individuals handled corals directly, but some were merely present while other handled the corals. Zoanthid samples from both commercial and private aquariums of affected persons were found to contain high levels of palytoxin. Chemical analysis confirmed 7.3 mg crude palytoxin/g wet weight of zoanthid tissue in one coral sample from a home aquarium and 6.2 mg crude palytoxin/g wet weight zoanthid in one coral sample from the aquarium shop. Three additional coral samples were nontoxic or only weakly toxic. Genetic analysis determined that both toxin-containing zoanthid samples were consistent with previous molecular identifications of a highly toxic variety of Palythoa species collected from similar aquarium-associated poisoning cases in Virginia, Ohio, and New York. The three additional nontoxic or weakly toxic zoanthid specimens were found to be genetically distinct.
CONCLUSIONS:
The risks for palytoxin exposure are unknown to many in the commercial aquarium and hobbyist communities. Activities that could potentially produce aerosols such as scrubbing or using hot water to remove zoanthids, mishandling zoanthids, or having an improperly functioning aquarium system might expose people and their pets to palytoxin when it is present in coral or water. The levels of palytoxin in the corals in this investigation exceeded those found in investigations of previous similar poisoning events (0.5 mg/g–3.5 mg/g wet weight). Hobbyist and commercial coral growers and the public health and health care provider communities would benefit from common recommendations on coral handling and decontamination practices.